Final phase ballistic strength & vertical jump training

In this study, 33 male university students participated in an eight-week program designed to help define the importance muscular overload in the final phases of the range of motion and the effect it has on vertical jump performance. The experimental device used was the DP Jump Stretch by Diversified Products. It is comprised of large elastic bands that attach to a support base. Due to the nature of the elastic compound, resistance for overload exercise is dispensed in an ever-increasing amount as the bands become stretched. Subjects were placed in one of four separate groups, each with a specific exercise protocol: (1) isokinetic knee strengthening at a low pace; (2) isokinetic knee strengthening at a quick pace; (3) vertical jumping; and (4) control. Data was collected on two test devices used in a pre and posttest: (1) the Cybex II isokinetic dyn6mometer which measured strength at 15, 30 and the strongest degree in the range of motion; and (2) Vertec jump device which measured vertical jump and reach height. After ANCOVA data reduction, results indicated that no significant differences existed between all groups.